Thyroid hormone concentrations in young, healthy, pretraining greyhounds

Total thyroxine (T(4)) concentrations were below the non-breed-specific reference range in 42 of 46 healthy young greyhounds (91.3 per cent) and 16 (34.8 per cent) were at or below the limit of detection of the assay. Free T(4) concentrations were below the standard reference interval in 20.5 per cent of the animals and 13 per cent were at or below the limit of detection of the assay. In contrast, all the dogs' total tri-iodothyronine concentrations were within or above the non-breed-specific reference range and 67 per cent were within the upper half. All the dogs' thyroid stimulating hormone concentrations were within the non-breed-specific reference range. The results show that young greyhounds have markedly lower total and free T(4) concentrations than other breeds, and neither analyte can reliably be used to investigate the hypothyroidism in this breed as values were found below the limit of detection of each respective assay.     

Erosive polyarthritis in two greyhounds

Clinical signs of disease, treatment, laboratory findings, and gross and microscopic changes of erosive polyarthritis in 2 Greyhounds are described. A microscopic feature that may help distinguish this condition from other types of arthritis is extensive necrosis of deep articular cartilage zones, with relative sparing of the more superficial surface cartilage. We believe that the disease in the 2 dogs of this report was identical to that encountered previously in Britain and Australia. Bacteriologic culture and serologic investigation failed to reveal the causative agent.     

Female pseudohermaphroditism in three sibling greyhounds

Three 18-month-old Greyhound siblings were found to have female pseudohermaphroditism. The disorder in sexual differentiation likely developed because the dam received testosterone proprionate for estrus prevention. All 3 siblings had a prepuce (no penis), vagina, uterus, and ovaries.     

The prevention of injuries in greyhounds

The analysis of 154 greyhound injuries shows a significant lower incidence of injuries in the case of proper preparing for the race. The prevention of injuries was carried out during the whole training-season. These optimally prepared dogs showed a better race performance and were able to take part in more races.     

Pharmacodynamic properties of succinylcholine in greyhounds

Succinylcholine is a depolarizing neuromuscular blocking drug, which is rapidly hydrolyzed by the enzyme pseudocholinesterase. In Greyhounds, the metabolism of certain drugs is atypical relative to other breeds, and it has been suggested that Greyhounds may be an atypical population, with lower pseudocholinesterase activity, slower hydrolysis of the drug succinylcholine, and a prolonged duration of action of the drug, compared with a mixed-breed control population. Six healthy adult Greyhounds and 6 healthy adult mixed-breed dogs were studied. Blood was drawn from each dog and analyzed for serum cholinesterase activity, and a biochemical profile was done to verify normal liver function. The dogs were anesthetized with methohexital (10 mg/kg) and isoflurane (1.25 minimal alveolar concentration) in 100% oxygen. Ventilation was controlled, fluids were administered IV (lactated Ringer solution, 10 ml/kg/h), and blood gases, blood pressure, and heart rate were monitored. The right hind limb was immobilized and a force transducer was used to monitor twitch strength of the interosseous muscle with supramaximal stimulation of the tibial nerve. Succinylcholine was administered to each dog 3 times at a dosage of 0.3 mg/kg. After drug administration, the time to 50% recovery of twitch strength (single twitch, 1/s), and 50% recovery of train-of-4 was determined. Subsequent doses were administered after complete recovery. The time to 50% recovery after succinylcholine administration in Greyhounds (38 minutes, dose 1, single twitch) was not significantly different than the time to 50% recovery in mixed-breed dogs (29 minutes, dose 1, single twitch), using either monitoring technique. Pseudocholinesterase activity was also not significantly different between the Greyhounds (1,685 mU/ml) and the mixed-breed dogs (1,588 mU/ml).(ABSTRACT TRUNCATED AT 250 WORDS)     

Postoperative bleeding in retired racing greyhounds

BACKGROUND: Some retired racing Greyhounds (RRG) that undergo surgery bleed excessively. Hypothesis: Greyhounds that bleed excessively will have one or more preoperative hemostatic abnormalities that can be used to predict the risk and severity of postoperative bleeding. ANIMALS: Eighty-eight RRG undergoing ovariohysterectomy or castration. METHODS: All dogs were evaluated preoperatively with a physical exam, CBC, platelet count, OSPT, APTT, platelet function with PFA-100(a); fibrinogen, d-dimer, plasminogen (Plmg), antiplasmin (AP), antithrombin (AT), and vWF concentration (vWF:Ag); vWF collagen binding assay (vWF:CBA), and Factor XIII assay. Assays were repeated in the dogs that bled, and in an age- and sex-matched control group of RRG. RESULTS: Twenty-six percent of the dogs had bleeding 36-48 hours after surgery. AP (P <.0001) and AT concentration (P= .007) were significantly lower, and vWF:CBA (P= .0284) was higher preoperatively in the dogs with excessive hemorrhage. A lower platelet count (P= .001) and hematocrit (P= .002), shorter OSPT (P= .0002) and higher plasma fibrinogen (P <.0001), and AP (P= .001) concentration were detected at the time of bleeding compared with preoperative values in the dogs that bleed excessively. The same findings were observed postoperatively for the control group, except for the decrease in hematocrit. CONCLUSIONS AND CLINICAL IMPORTANCE: The results indicate that this excessive postoperative bleeding is not attributable to a primary or secondary hemostatic defect, but could result from altered fibrinolysis.     

Intracranial fusariosis: a novel cause of fungal meningoencephalitis in a dog

The Fusarium species are a group of saprophytic fungal organisms that are occasionally the cause of opportunistic infections in humans and animals. Central nervous system disease associated with a Fusarium species is most commonly described in horse, resulting in equine leukoencephalomalacia. This report describes a 2-year-old, spayed, female German Shepherd Dog with meningoencephalitis secondary to infection with Fusarium spp. Meningoencephalitis in dogs secondary to a species of Fusarium has not been previously reported. The diagnosis was made based on the histopathologic examination of brain tissues postmortem and special immunohistochemical stains specific for Fusarium solani. The clinical signs in this dog were indicative of multifocal brain disease and included seizures and a paradoxical vestibular syndrome. The clinical findings, diagnostic and histopathologic test results, and the comparative characterizations of other disseminated fungal diseases, especially aspergillosis, are described.